PROJECT SUMMARY/ABSTRACT The heart is arguably one of the most critical organs of the human body as it drives the distribution of oxygen, nutrients, signaling factors, and heat throughout the entire body. Any form of cardiac dysfunction can thus compromise an individual?s longevity and quality-of-life; severe cases lead to organ failure and death. According to the 2017 American Heart Association (AHA) annual report, heart disease remains the number one cause of death in the United States. This unfortunate statistic highlights the need for new and innovative approaches to understanding and treating cardiac disease. To this end, murine models of cardiac disease have played a crucial role in systematically exploring the complex underlying mechanisms to cardiac pathophysiology. Unfortunately, the most commonly used in vivo imaging tool to measure heart function in these mice, high-frequency linear- array ultrasound, relies heavily on idealized geometries of the left-ventricle to estimate function metrics. We have recently developed and validated a four-dimensional ultrasound (4DUS) technique that uses this same underlying technology, but provides volumetric information of the murine heart across a representative cardiac cycle. Following in the objective set by the National Heart, Lung, and Blood Institute (NHBLI) to ?develop and optimize novel diagnostic and therapeutic strategies to prevent, treat, and cure HLBS diseases? and subsequent Compelling Question ?How can imaging technology be leveraged to identify clinically useful markers of metabolic syndrome and cardiopulmonary disease??, the proposed work will build upon this 4DUS technique to create a platform for researchers to assess cardiac function in their models more comprehensively than standard cardiac metrics (e.g. transmural strain, segmented chamber filling/ejection patterns, etc.) and correlate those measurements to localized cellular-level information. We plan to accomplish this goal through the following two AIMS: 1) Refine and validate our 4DUS analysis software to provide reliable metrics of cardiac kinematics, which can be robustly compared across cohorts of murine 4DUS data; 2) Assess myocardial dysfunction by correlating regional strain and proteomic profiles in three separate models of cardiac disease. This fellowship research and training will be carried out at Purdue University under the thoughtful supervision of Drs. Craig Goergen, I-wen Wang, Jessica Ellis, and Mauro Costa. This work using novel methodologies will lead to enormous advancements in our understanding on how spatial specific metabolic profiles are associated with heart dysfunction in murine models of congenital heart disease and myocardial infarction. Further widespread adoption this platform will provide an expandable approach to study the role of spatial regulation in other cardiac models of heart disease and increase the scientific reach of the NHBLI research community.